I. FIELD OF THE INVENTION
The present invention relates to an apparatus for handling sod, either in the laying of sod or the harvesting of sod, and more particularly to an apparatus which provides standing supports for workers engaged in manually handling the sod.
II. DESCRIPTION OF THE PRIOR ART
In the past, newly developed large open areas have been planted with grass seed and covered with straw in order to cover the area with growing grass. Grass has been preferable for large open areas because of its aesthethic appearance and also because of its ecological characteristics of holding ground water and preventing erosion of the soil. However, in recent years most businesses and consumers have elected to pay a slight additional charge to have sod laid on these large open areas in order to achieve immediate aesthetic and conservation benefits. The harvesting and laying of sod has become a relatively large business in view of this consumer and business demand.
At the present time a large majority of all sod is cut in rectangular strips which are then piled on top of each other and carried on pallets to the area of installation. Typically, these pieces of sod are unloaded from the pallet one piece at a time by indivicual workers. These workers must walk behind a forklift, tractor or other vehicle which carries the pallets of sod over the area to be covered. The workers must remove each individual piece of sod from the pallet and deposit it on the ground, while taking care to place the peice of sod immediately adjacent to and abutting previously laid pieces of sod. This is a back-breaking procedure which requires a great amount of energy and forces the workers to walk great distances while carying the heavy pieces of sod.
Prior inventors have attempted to solve the problem of laying and harvesting sod by mechanizing the process. These attempts have been only marginally successful, primarily because the machinery which has been developed is extremely complex and expensive to produce. Since most of the sod laying is done by small independent contractors, it is not unusual for the contractor to forego expensive capital investments and instead to rely upon expensive personal labor retained on a day-to-day basis.
White, in U.S. Pat. No. 4,149,640, discloses an apparatus for laying sod which includes a self-propelled wheeled frame having an endless loop conveyor oriented in a generally horizontal position on the top thereof. A drive mechanism is provided adjacent the rear end of the conveyor and a slide or chute is provided for receiving the pieces of sod from the conveyor drive mechanism and depositing them on the ground. White maintains the stacked orientation of the pieces of sod on the conveyor until each piece is removed sequentially by the sod driving mechanism for being deposited upon the chute. While the White disclosure does provide mechanical assistance in laying the sod, it is still imperative that workers walk beside the motorized frame in order to assist in the handling of the sod, because the flow rate of the sod pieces along the conveyor and onto the drive mechanism is not well coordinated. White furthermore teaches the concept of maintaining the stacked relationship of the pieces of sod while tipping the entire stack to the horizontal position. Although this appears to be workable in theory, in practice the sod is very difficult to handle in this manner. The sod is extremely heavy, especially when wet, and the mechanical aspects of rotating the pile of sod and moving it along the conveyor requires extraordinarily heavy construction and large amounts of energy.
The disclosure of White should be contrasted with the present invention which is designed to receive the upstanding pallets of sod adjacent to the front thereof. The present invention minimizes the manual labor required by using it only for removing the pieces of sod from the pallets and depositing the sod onto the conveyor. The sod is then transported along the conveyor in a generally rearward direction (when laying the sod). The speed of the wheeled frame is adjusted so that the sod will be deposited upon the ground without undue handling and placement. Therefore, the present invention attempts to utilize a limited amount of manual labor while maintaining the constant flow and placement of sod from the pallet onto the ground.
Strader, in U.S. Pat. No. 684,125, discloses a cart having a rear ramp employing a plurality of frictionless rollers which are used to assist in the unloading of articles carried within the cart. This device does not disclose the use of any generally horizontal conveyor, nor does it disclose the concept of placing the pallets of sod adjacent the front edge of a conveyor which is oriented suitably for allowing manual labor to remove the sod from the pallet and place the sod over the conveyor.
Curtis, in U.S. Pat. No. 3,220,527, discloses a portable roller-conveyor for handling meat or other related products. The rollers are attached to a frame to form an inclined conveyor of the size typically used for unloading products from a truck or tractor-trailer. The frame includes several wheels for allowing the apparatus to be moved between operating locations. While Curtis does disclose an inclined conveyor comprising a plurality of rollers, there is absolutely no teaching that these rollers may be used for depositing the sod upon the ground nor is there any teaching relating to juxtaposing the pallet of sod adjacent to both the front end of the conveyor rollers and foot supports for the manual laborers.
Various other conveyors are disclosed by Swara in U.S. Pat. No. 3,792,500; Woldring in U.S. Pat. No. 2,347,308; Backart in U.S. Pat. No. 2,489,947; Sullivan in U.S. Pat. No. 3,059,747; Smith in U.S. Pat. No. 2,075,833; and Lister in U.S. Pat. No. 1,050,478. These references are generally related to the movement of articles along conveyors, and they contain teachings as to the use of foot supports for manual laborers involved in the loading or unloading of the articles to be moved along the conveyor.